C++ opencv ffmpeg图片序列化实现代码解析

ffmpeg -y -framerate 10 -start_number 1 -i E:\Image\Image_%d.bmp E:\test.mp4
-y 			 表示输出时覆盖输出目录已存在的同名文件
-framerate 10		 表示视频帧率
-start_number 1		 表示图片序号从1开始
-i E:\Image\Image_%d.bmp 表示图片输入流格式 

SHELLEXECUTEINFO ShExecInfo = { 0 };
ShExecInfo.cbSize = sizeof(SHELLEXECUTEINFO);
ShExecInfo.fMask = SEE_MASK_NOCLOSEPROCESS;
ShExecInfo.hwnd = NULL;

ShExecInfo.lpVerb = L"open";
ShExecInfo.lpFile = L"ffmpeg.exe";
ShExecInfo.lpParameters = L"ffmpeg.exe -y -framerate 10 -start_number 1 -i E:\Image\Image_%d.bmp E:\test.mp4";

ShExecInfo.lpDirectory = NULL;
ShExecInfo.nShow = SW_HIDE;//窗口状态为隐藏
ShExecInfo.hInstApp = NULL;
if (ShellExecuteEx(&ShExecInfo))
{
  if (ShExecInfo.hProcess)
  {
    WaitForSingleObject(ShExecInfo.hProcess, INFINITE);
  }
}

cv::Mat image;
int fps = 10;//视频帧率

/*cv::VideoWriter::fourcc('M', 'P', '4', 'V')生成MP4格式视频*/
/*cv::VideoWriter::fourcc('M', 'J', 'P', 'G')生成avi格式视频,大小比'X', 'V', 'I', 'D'大*/
/*cv::VideoWriter::fourcc('X', 'V', 'I', 'D')生成avi格式视频*/
cv::VideoWriter writer("video_out.avi", cv::VideoWriter::fourcc('M', 'J', 'P', 'G'),
            fps, cv::Size(3840, 2748)/*图片大小，一定不能出错*/, 0);

for (size_t i = 1; i <= 100; i++)
{
  image = cv::imread("Image_" + std::to_string(i) + ".bmp", cv::IMREAD_GRAYSCALE);
  if (!image.empty())
  {
    writer.write(image);
  }
}